A gas turbine engine includes a compressor section and a combustion section with a scroll, a scroll baffle, a combustor, and a combustor case. The scroll defines an interior scroll flow path. The scroll baffle surrounds the scroll to define a scroll cooling passage. The combustor case surrounds the combustor and the scroll baffle to define a collector space. Moreover, the engine includes a turbine section with a turbine rotor and a turbine rotor blade shroud that includes a shroud cooling passage. The compressor flow path is fluidly connected to the scroll for cooling the scroll. Also, the scroll cooling passage is fluidly connected to the shroud cooling passage for cooling the turbine rotor blade shroud. Furthermore, the shroud cooling passage is fluidly connected to the collector space. flow from the collector space flows into the combustor, along the interior scroll flow path, toward the turbine rotor.
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10. A component for a gas turbine engine comprising:
a scroll with a scroll peripheral wall having an inner surface and an outer surface, the inner surface defining an interior scroll flow path that extends generally in a circumferential direction about a longitudinal axis;
a scroll baffle that surrounds at least part of the scroll, the scroll baffle including a baffle peripheral wall having an inner surface and an outer surface, the inner surface of the baffle peripheral wall facing the outer surface of the scroll peripheral wall; and
a scroll cooling passage defined between the outer surface of the scroll peripheral wall and the inner surface of the baffle peripheral wall, the scroll cooling passage including an inlet and an outlet and having a generally toroidal shape with an inner diameter area and an outer diameter area, the scroll cooling passage configured to direct a flow from the inlet to the outlet in a toroidal direction about the scroll from the inner diameter area, toward the outer diameter area, and back toward the inner diameter area to cool the scroll;
the scroll peripheral wall being continuous along the scroll cooling passage between the inlet and the outlet, the scroll peripheral wall blocking the flow from entering the interior scroll flow path; and
the baffle peripheral wall being continuous along the scroll cooling passage between the inlet and the outlet.
1. A gas turbine engine comprising:
a compressor section that defines a compressor flow path;
a combustion section that includes a scroll, a scroll baffle, a combustor, and a combustor case, the scroll defining an interior scroll flow path, the scroll baffle surrounding at least part of the scroll to define a scroll cooling passage between the scroll baffle and the scroll, the combustor case surrounding the combustor and at least part of the scroll baffle to define a collector space between the combustor case and the scroll baffle; and
a turbine section with a turbine rotor and a turbine rotor blade shroud, the turbine rotor blade shroud including a shroud cooling passage;
the compressor section being coupled to the combustion section with the compressor flow path fluidly connected to the scroll cooling passage to direct flow from the compressor flow path along the scroll cooling passage to cool the scroll;
the combustion section being coupled to the turbine section with the scroll cooling passage fluidly connected to the shroud cooling passage to direct flow from the scroll cooling passage along the shroud cooling passage to cool the turbine rotor blade shroud;
the shroud cooling passage being fluidly connected to the collector space; and
the collector space being fluidly connected to the interior scroll flow path such that flow from the collector space flows into the combustor, along the interior scroll flow path, toward the turbine rotor.
16. A component for a gas turbine engine comprising:
a combustor and a combustor case;
a scroll with a scroll peripheral wall having an inner surface and an outer surface, the inner surface defining an interior scroll flow path that extends generally in a circumferential direction about a longitudinal axis;
a scroll baffle that surrounds at least part of the scroll, the scroll baffle including a baffle peripheral wall having an inner surface and an outer surface, the inner surface of the baffle peripheral wall facing the outer surface of the scroll peripheral wall, the combustor case surrounding the combustor and at least part of the scroll baffle to define a collector space between the combustor case and the scroll baffle;
a scroll cooling passage defined between the outer surface of the scroll peripheral wall and the inner surface of the baffle peripheral wall, the scroll cooling passage including an inlet and an outlet, the scroll cooling passage configured to direct a flow from the inlet to the outlet to cool the scroll;
the scroll peripheral wall being continuous along the scroll cooling passage between the inlet and the outlet, the scroll peripheral wall blocking the flow from entering the interior scroll flow path;
further comprising a turbine section with a turbine rotor and a turbine rotor blade shroud, the turbine rotor blade shroud including a shroud cooling passage, the shroud cooling passage being fluidly connected to the collector space such that the flow from the shroud cooling passage is received in the collector space;
wherein at least one of the scroll and the scroll baffle are attached to the turbine rotor blade shroud to fluidly connect the outlet of the scroll cooling passage to the shroud cooling passage;
wherein the shroud cooling passage is configured to receive the flow from the scroll cooling passage to cool the turbine rotor blade shroud;
and the collector space being fluidly connected to the interior scroll flow path such that the flow from the collector space flows through the combustor and into the interior scroll flow path.
2. The gas turbine engine of
3. The gas turbine engine of
4. The gas turbine engine of
wherein the scroll includes a peripheral wall that is continuous and that is a barrier separating the scroll cooling passage from the interior scroll flow path.
5. The gas turbine engine of
6. The gas turbine engine of
7. The gas turbine engine of
further comprising an inlet flow control member disposed proximate an inlet of the scroll cooling passage, the inlet flow control member including a plurality of vanes that are spaced apart and arranged in a circumferential direction about the longitudinal axis proximate the inlet of the scroll cooling passage;
wherein the plurality of vanes direct flow into the inlet of the scroll cooling passage.
8. The gas turbine engine of
further comprising an outlet flow control member disposed proximate an outlet of the scroll cooling passage;
wherein the outlet flow control member is operable to meter the flow through the scroll cooling passage.
9. The gas turbine engine of
further comprising a rear member disposed between the plenum and the collector space, the rear member including at least one opening allowing flow from the plenum, through the rear member, and into the collector space.
11. The component of
wherein at least one of the scroll and the scroll baffle are attached to the turbine rotor blade shroud to fluidly connect the outlet of the scroll cooling passage to the shroud cooling passage;
wherein the shroud cooling passage is configured to receive the flow from the scroll cooling passage to cool the turbine rotor blade shroud.
12. The component of
13. The component of
wherein the scroll baffle includes a first member and a second member that cooperate to surround at least part of the scroll, an opening defined in the scroll baffle that provides fluid access for the flow from the outlet of the interior scroll flow path to be directed toward a turbine rotor.
14. The component of
wherein the junction extends in the circumferential direction about the scroll baffle.
15. The component of
wherein the baffle peripheral wall encompasses the inlet;
wherein the baffle peripheral wall is attached to the scroll peripheral wall and closes off the scroll cooling passage proximate the inlet.
17. The component of
18. The component of
wherein a radial cross section of the collector space is defined between the outer surface of the baffle peripheral wall and an inner surface of the combustor case; and
wherein an area of the radial cross section grows progressively larger as the collector space extends in the circumferential direction about the scroll baffle.
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The present disclosure generally relates to a gas turbine engine and, more particularly, to a turbine scroll assembly for a gas turbine engine.
Gas turbine engines are generally used in a wide range of applications, such as aircraft engines and auxiliary power units. In a gas turbine engine, air is compressed in a compressor, mixed with fuel, and ignited in a combustor to generate hot combustion gases, which flow downstream into a turbine section.
During operation of the engine, temperatures within and surrounding the combustion section can be very high. Thus, it is desirable to regulate the operating temperature of certain engine components, particularly those within the mainstream hot gas flow path. Some engines include certain structures and features that provide cooling to these components. However, many of these reduce the efficiency of the engine. Also, some cooling features may not be useful in certain operating conditions. Additionally, structures with these types of cooling features may be especially difficult to manufacture.
Accordingly, it is desirable to provide a gas turbine engine with improved cooling features within and/or surrounding the combustion section. Furthermore, other desirable features and characteristics of the present disclosure will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.
In one embodiment, a gas turbine engine is disclosed that includes a compressor section that defines a compressor flow path. The gas turbine engine also includes a combustion section that includes a scroll, a scroll baffle, a combustor, and a combustor case. The scroll defines an interior scroll flow path. The scroll baffle surrounds at least part of the scroll to define a scroll cooling passage between the scroll baffle and the scroll. The combustor case surrounds the combustor and at least part of the scroll baffle to define a collector space between the combustor case and the scroll baffle. Moreover, the gas turbine engine includes a turbine section with a turbine rotor and a turbine rotor blade shroud. The turbine rotor blade shroud includes a shroud cooling passage. The compressor section is coupled to the combustion section with the compressor flow path fluidly connected to the scroll cooling passage to direct flow from the compressor flow path along the scroll cooling passage to cool the scroll. Also, the combustion section is coupled to the turbine section with the scroll cooling passage fluidly connected to the shroud cooling passage to direct flow from the scroll cooling passage along the shroud cooling passage to cool the turbine rotor blade shroud. Furthermore, the shroud cooling passage is fluidly connected to the collector space. The collector space is fluidly connected to the interior scroll flow path such that flow from the collector space flows into the combustor, along the interior scroll flow path, and toward the turbine rotor.
In another embodiment, a component for a gas turbine engine is disclosed that includes a scroll with a scroll peripheral wall having an inner surface and an outer surface. The inner surface defines an interior scroll flow path that extends generally in a circumferential direction about a longitudinal axis. Also, a scroll baffle surrounds at least part of the scroll. The scroll baffle includes a baffle peripheral wall having an inner surface and an outer surface. The inner surface of the baffle peripheral wall faces the outer surface of the scroll peripheral wall. Moreover, a scroll cooling passage is defined between the outer surface of the scroll peripheral wall and the inner surface of the baffle peripheral wall. The scroll cooling passage includes an inlet and an outlet. The scroll cooling passage is configured to direct a flow from the inlet to the outlet to cool the scroll. The scroll peripheral wall is continuous along the scroll cooling passage between the inlet and the outlet. The scroll peripheral wall blocks the flow from entering the interior scroll flow path.
The present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
The following detailed description is merely exemplary in nature and is not intended to limit the present disclosure or the application and uses of the present disclosure. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
Broadly, exemplary embodiments disclosed herein include gas turbine engines having improved cooling characteristics. Methods of manufacturing the gas turbine engines are also disclosed. In particular, exemplary embodiments include a combustion section with a turbine scroll assembly that includes a scroll cooling passage. The scroll cooling passage provides improved cooling of the turbine scroll. Other cooling features are also disclosed for cooling other components of the gas turbine engine. Additional details of the present disclosure will be discussed below.
The gas turbine engine 100 has an overall construction and operation that is generally understood by persons skilled in the art. The gas turbine engine 100 may be disposed in an engine case 101 and may include an intake section 120, a compressor section 130, a combustion section 140, a turbine section 150, and an exhaust section 160. A longitudinal axis 180 and a radial axis 190 are also included for reference purposes. The radial axis 190 is perpendicular to the longitudinal axis 180. It will be appreciated that a rearward longitudinal direction is defined generally from the intake section 120 toward the exhaust section 160 along the longitudinal axis 180. Conversely, a forward longitudinal direction is defined generally from the exhaust section 160 toward the intake section 120 along the longitudinal axis 180. An outboard radial direction is defined generally along the radial axis 190, away from the longitudinal axis 180. Conversely, an inboard radial direction is defined generally along the radial axis 190, toward the longitudinal axis 180. Moreover, a circumferential direction is defined generally extending around the longitudinal axis 180.
The intake section 120 may draw in and accelerate air toward the compressor section 130. The compressor section 130 may include a series of compressors that raise the pressure of the air directed into it from the intake section 120. The compressors may direct the compressed air into the combustion section 140. In the combustion section 140, the high-pressure air is mixed with fuel and combusted. The combusted air is then directed into the turbine section 150. The combusted air from the combustion section 140 causes one or more rotor assemblies to rotate a main engine shaft 141 for energy extraction. The air is then exhausted through a propulsion nozzle disposed in the exhaust section 160 to provide additional forward thrust.
Referring now to
As shown in
As shown in
As shown in
Referring to
Also shown in
Furthermore, the peripheral wall 226 of the scroll 224 may define a scroll inlet 228 and a scroll outlet 230 of an interior scroll flow path that is represented by arrow 221 in
Referring to
Referring to
As shown in
Referring to
The baffle 250 may correspond in shape to that of the scroll 224; however, the baffle 250 may be slightly larger than that of the scroll 224. As shown in
Additionally, as shown in
Referring now to
Generally, the compressor section 130 may include an impeller 300 that rotates about the longitudinal axis 180. The impeller 300 may be mounted to a shaft 302 that extends along the axis 180. The compressor section 130 may additionally include a shroud 304 with an inner surface that faces the impeller 300. Moreover, the compressor section 130 may include a support structure 308 that is connected and that supports the shroud 304 and/or other adjacent components. Furthermore, the compressor section 130 may include an end member 310.
As the impeller 300 rotates about the axis 180, air is compressed and flows along a compressor flow path 306. Flow along this path is indicated by arrow 312. As shown, the compressor flow path 306 is defined along an inner surface of the shroud 304, along the support structure 308, and along the end member 310.
Additionally, the compressor section 130 may be fixed to the turbine scroll assembly 206. More specifically, the support structure 308 may be attached to the forward flange 262 of the baffle 250. Also, the end member 310 may be attached to the forward flange 241 of the scroll 224. Accordingly, as shown in
Furthermore, the support structure 308 of the compressor section 130 may be fixed to a forward end 276 of the combustor case 202. In some embodiments, the support structure 308 may be a barrier that further defines areas of the collector space 270 that are disposed forward of the scroll assembly 206.
The turbine section 150 of the engine 100 includes a rotor 244 with a plurality of rotor blades, one of which is indicated at 242. The turbine section 150 may additionally include a rotor blade shroud 316 and a support structure 318. The rotor 244 may be mounted for rotation about the axis 180. The rotor 244 may be supported on the shaft 302.
Additionally, the rotor blade shroud 316 may include a shroud cooling passage 320 extending therethrough. The shroud cooling passage 320 may include an inlet 322 and an outlet 324. The passage 320 may additionally include one or more turns 326, 328, 330, which re-direct the air flowing through the passage 320. As shown in
The turbine section 150 may also include an exhaust passage 340 that is fluidly connected to the outlet 230 of the scroll 224. The exhaust passage 340 receives exhaust gas flow from the interior 240 of the scroll 224. A turbine nozzle 342 may be disposed within the exhaust passage 340.
Furthermore, the support structure 318 of the turbine section 150 may be fixed to a rear end 278 of the combustor case 202. Also, in some embodiments, a support structure 344 extends between and connects support structure 318 and the outer wall structure 327 of the shroud cooling passage 327. Support structure 344 may include one or more perforations 350 which allows the cooling air flowing through the shroud cooling passage 320 to exit the outlet 324 and pass through the support structure 344. A plurality of the perforations 350 are shown in
In some embodiments, the inner surface of the combustor case 206, the support structure 344, the rearward side of the baffle 250 and a portion of the rotor blade shroud 316 may cooperate to define a rear plenum 346. As shown in
Thus, during operation of the engine 100, the compressor section 130 may compress and move air along the compressor flow path 306. The compressor section 130 may direct flow toward outlet 307 and into the inlet 265 of the scroll cooling passage 252. The air may flow substantially in a toroidal direction about the scroll 224 as indicated by arrows 348. In other words, and in reference to
As mentioned, the engine 100 includes various cooling passages, pathways, plenums, collectors, etc. that provide a cooling effect for respective structures of the engine 100. They may provide various advantages.
For example, the scroll cooling passage 252 may receive core flow from the compressor section 130 and provide cooling to the scroll 224. In some embodiments, the scroll cooling passage 252 may be directly attached to the compressor flow path 306 such that the scroll cooling passage 252 receives core flow from the compressor section 130. This provides more cooling capability than can be accomplished by introducing core flow bleed air into the scroll cooling passage 252. In other words, the full core flow from the compressor section 130 may be maintained and delivered to the scroll cooling passage 252 to cool the scroll 224. In some embodiments, the scroll cooling passage 252 may receive substantially all of the core flow from the compressor section 130.
Also, in some embodiments, the peripheral wall 226 of the scroll 224 may be continuous along the scroll cooling passage 252 between the inlet 265 and the outlet 263. Likewise, the peripheral wall 251 of the baffle 250 may be continuous along the scroll cooling passage 252 between the inlet 265 and the outlet 263. As such, the peripheral wall 226 may act as a barrier, blocking the flow along the scroll cooling passage 252 from entering the interior scroll flow path 221. Similarly, the peripheral wall 251 may act as a barrier, blocking the flow along the scroll cooling passage 252 from entering the outer space 270 and the rear plenum 346. In other words, the scroll assembly 206 need not include effusion cooling holes that extend through the thickness of the peripheral wall 226 of the scroll 224 and/or impingement holes in the peripheral wall 251 of the baffle 250 (i.e., the peripheral walls 226, 251 may be continuous, unperforated, or otherwise free of such effusion or impingement cooling apertures). The peripheral walls 226, 251 may be continuous in both the toroidal direction as well as the circumferential direction. Thus, the flow through the scroll cooling passage 252 may cool the scroll 224 via convective cooling and flow along the exterior surface of the peripheral wall 226 in the toroidal direction (i.e., backside convective cooling of the scroll 224).
Because the peripheral walls 226, 251 are continuous (i.e., without effusion and/or impingement cooling holes), the scroll assembly 206 may exhibit increased strength and robustness. Also, the scroll assembly 206 may have increased manufacturability since effusion and/or impingement holes may be unnecessary. Furthermore, flow through the scroll assembly 206 may be more controllable since the cooling passage 252 relies on convective cooling instead of effusion and/or impingement cooling. Additionally, cooling of the scroll assembly 206 may be ensured since it may not include effusion and/or impingement holes, which may be susceptible to clogging or blockage due to dust, debris, etc.
It will be appreciated that, in other embodiments, effusion and/or impingement holes may be included. For example, these holes may be included in localized areas to provide localized cooling to predetermined areas (e.g., areas of the scroll).
Furthermore, the scroll cooling passage 252 may be fluidly connected to the shroud cooling passage 320 of the rotor blade shroud 316. Accordingly, core flow from the compressor section 130 may be used to cool both the scroll 224 as well as the rotor blade shroud 316. This may increase cooling efficiency. Also, this may allow the engine 100 to be relatively compact and less complex.
Additional example embodiments of the present disclosure will now be discussed. In some embodiments, the outer surface 268 of the scroll 224 and/or the inner surface 266 of the baffle 250 may include dimples, bumps, projections, or other surface variations. These features may be configured to reduce or eliminate any boundary layer of the flow through the scroll cooling passage 252 to increase heat transfer. These surface features may also be included at local areas of the scroll cooling passage 252 to increase heat transfer at those areas. Additionally, standoff features may be included that are used to control the radial gap between the outer surface 268 of the scroll 224 and the inner surface 266 of the baffle 250. These standoff features could be dispersed on the outer surface 268 of the scroll 224 and/or the inner surface 266 of the baffle 250. The plurality of dispersed standoff features could essentially be radial structures that could be localized structures, continuous rib-like structures, or another structure. These structures could also be used to provide local flow control of the scroll cooling passage 252 for improving the scroll 224 cooling. In some embodiments, the turbine rotor blade shroud outer cooling wall 352 may include dimples, bumps, projections, or other surface variations. These features may be configured to reduce or eliminate any boundary layer of the flow through the shroud cooling passage 320 to increase heat transfer.
Referring now to
The scroll cooling passage 1252 is shown in
As shown in
Additionally, the engine 1100 may include the inlet flow control member 1402 mentioned above. The inlet flow control member 1402 may be annular and may extend circumferentially about the longitudinal axis 1108. Additionally, the inlet flow control member 1402 may include a plurality of vanes 1404, 1406, two of which are indicated in
Moreover, the engine 1100 may further include the outlet flow control member 1410 mentioned above. The outlet flow control member 1410 may be disposed proximate an outlet 1263 of the scroll cooling passage 1252. The outlet flow control member 1410 may be annular and may extend circumferentially about the longitudinal axis 1180. In some embodiments, the outlet flow control member 1410 may include a plurality of apertures, two of which are indicated at 1412a and 1412b in
Furthermore, as shown in
Accordingly, the embodiment of
While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. For example, the inlet flow control member 1402 of
Smoke, Jason, Jan, David K., Matwey, Mark
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